Trammel scale and layout tool



March 14, 1961 P. G. ZURCHER 2,974,416

TRAMMEL SCALE AND LAYOUT TOOL Filed July 2, 1959 MRI MM PA UL 6. Zu/e 0/452 IN VEN TOR.

ATZOR VEV United States Patent i 2,974,416 TRAMMEL SCALE AND LAYOUT TOOL Paul G. Zurcher, 306 N. Pleasant Ave., Ridgewood, NJ. Filed July 2', 1959, Ser. No. 824,639

7 Claims. (Cl. 33-27 This invention relates to mechanics and-engineers tools and is directed particularly to a trammel scale and layout tool or beam compass having a plurality of parts which can be used singly or in combination with one or more other parts to provide a multiplicity of tools.

The principal object of the invention is to provide a combination tool of the above nature which, besides its use as a beam compass, is adapted for use of its individual parts singly or in combination as a scale, a pencil, a scribe and a depth gage, thereby providing the various individual tools commonly used in woodworking or metalworking layout.

Another object of the invention is to provide a combination tool of the character described which is simple and inexpensive enough to be used effectively by students, yet which is precise and otherwise practical for use by the skilled craftsman.

Still another object is to provide a combination tool of the above nature which will be easy to manipulate, attractive in appearance and long-wearing in use.

Other objects, features and advantages of the invention will be apparent from the following description when read with reference to the accompanying drawings. In the drawings, wherein like reference numerals denote corresponding parts throughout the several views:

Fig. 1 illustrates, in perspective, one of the trammel attachment members and shows, in exploded relation, how the various cornbinative tools can be fitted thereto,

Fig. 2 is a partial elevational view illustrating how a flat scale can be assembled to one of the trammel attachment members comprising the invention,

Fig. '3 is a vertical cross-sectional view taken along the line 3-3 of Fig. 2, i

Fig. 4 is a front elevational view illustrating how two trammel attachment members can be connected to two triangular scale members and join them together in endto-end relation by use of a scribing tool, to provide a beam compass or the like of extended length, and

Fig. 5 is a cross-sectional View taken along the line 55 of Fig. 4 in the direction of the arrows.

Referring now in detail to the drawings, the combination trammel scale and layout tool comprising the invention consists of a pair of trammel attachment members 10, 11 having means for adjustably receiving and securing to, selectively, a fiat scale 12, or a triangular scale 13, alone or in combination with a scribe rod 14, for the uses and purposes hereinbelow more fully described.

The trammel attachment members 10, 11, which are preferably molded of a clear synthetic plastic material for economy and to allow easy reading of the scales 12 or 13 when attached thereto, are generally in the form of an isoceles triangular block, the base of which is rounded as indicated at 15 and extends into a circular flat surface portion 16 of comparatively small area. The apex or upper end of the attachment members 11 are likewise rounded as indicated at 17 to terminate in a circular flat surface portion 18 similar to and substantially parallel to the base surface portion 16.

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The trammel attachment members 10, 11 are formed with substantially triangular parallel front and back surfaces 19, 20 and downwardly diverging side surfaces 21, 22.

A vertical through slot 23 is provided in the trammel attachment members 10, 11 extending at a central location between the side surfaces 21, 22 thereof, said slot being adapted to slidingly receive the fiat scale 12- as illustrated in Fig. 2. The slot 23 extends, centrally along its vertical length, into a round through opening portion 24 adapted to slidingly receive the extension bar 41.

The elongated triangular scale 13 is integrally formed and comprises downwardly-divergent side portions 25, 26, a base portion 27 formed with a central end-to-end arcuate recess 28, and an end-to-end head portion 29 substantially of square cross-sectional shape. The side portions of the scale 13 are marked off in inches and fractions thereof, or other appropriate units of measurement, as indicated at 30.

Means is provided in the trammel attachment members 10, 11 to slidingly receive a triangular scale 13. To this end the attachment members 10, 11 are formed with front-to-back through openings each having downwardly-divergent side walls 32 extending along their upper ends into an upper opening portion 33 of inverted U- shaped cross-section. The lower end or base of each opening is generally of the shape of an inverted V in cross-section, the apex of the V being arcuately recessed, as indicated at 34.

Means is provided for securing the fiat scale 12, the triangular scale 13 or the extension bar 41, selectively, in adjusted position in one or both of the trammel attachment members 10, 11, to which upper end the upper ends of said attachment members are vertically drilled and tapped, as indicated at 18 in Fig. 5, to receive a knurled headed thumb screw 36. The thumb screw 36 can be turned down to lock the scale 12, 13 or theextension bar 41 down in place in its respective slide, slot or opening, 23, 32 and 24. As illustrated in Fig. 5, a scribe rod 14 will fit between the arcuaterecess 34 and the arcuate recess 28 in the base portion of the triangular scale 13 for locking said scribe rod in place together with 'the scale when desired. If the straight end of the scribe rod is allowed to project it can be used as a depth gage with respect to the end of the triangular scale, and the fiat scale 12 can be used in such instances to set to the depth measurement required.

As best illustrated in Fig. 4, the trammel attachment member 10 is provided with a metal stem 35' projecting centrally from its lower end and terminating in a.drilled and slotted end portion 36 within which a steel pin 37 can be seated and frictionally held when using the tool as a beam compass either for drawing or for layout work on metal or other hard surfaces. The trammel attachment member 11 is provided with a metal stem 38 projecting centrally from its lower end and terminating in a screwon chuck 39 adapted to receive and hold therein a pencil lead or steel 40.

In another use of the combination instrument comprising the invention, both trammel attachment members can be applied to a scale, preferably the triangular scale rately as a pencil, and the trammel attachment member 10 can be used separately as a scriber. The shape of the triangular scale 13 makes it easy to handle separately as a drafting or measuring instrument, the head portion 29 thereof being convenient to grasp and the deep recess 28 thereof making the scale unusually light, whether made of a metal such as aluminum or a durable synthetic plastic.

While I have illustrated and described herein one form in which my invention may conveniently be embodied in practice, it is to be understood that this form is presented by way of example only and not in a limiting sense. The invention is limited only by the scope and spirit of the following claims.

What I claim as new and desire to secure by Letters Patent is:

l. A trammel scale and layout combination tool comprising a pair of trammel attachment members, an elongated integrally formed angular scale having downwardlydivergent side scale Walls, a coextensive head portion of substantially square cross-section and a coextensive base portion formed with a longitudinal central end-to-end recess of arcuate cross-sectional shape, each of said trammel attachment members having a central horizontally extending through opening for slidingly receiving said angular scale, means for securing said angular scale in adjusted position with respect to each of said attachment members, said opening in each of said trammel members comprising an upwardly-projecting attachment member portion of inverted V-shape adapted to fit into the central groove of said angular scale, said attachment portion having an arcuate recess formed along the apex of said portion of inverted V-shape, and a metal scribe having a cylindrical body portion seatable in said arcuate recess and in the central groove of said angular scale.

'2. The invention as defined in claim 1 wherein said securing means comprises a thumb screw threaded through the top of each of said trammel attachment members and arranged to press against the top of the head portion of said angular scale when received in said central openings, and wherein said openings are large enough to allow compression of said body portion of said scribe between said arcuate recess of said attachment porltion and the central arcuate recess of said angular sea e.

3. The invention as defined in claim 1 including a stem member extending downwardly from the lower end of. each of said trammel members, a pencil lead removably attached to the outer end of one of said stern members and a steel pin removably attached to the outer end of the other of said stem members.

4. A trammel scale and layout combination tool comtral end-to-end recess of arcuate cross-sectional shape,

each of said trammel attachment members having a central horizontally extending through opening for slidingly receiving said angular scale, means for securing said angular scale in adjusted position with respect to each of said attachment members, said opening in each of said trammel members comprising an upwardly-projecting attachment member portion of inverted V-shape adapted to fit into the central groove of said angular scale, a through vertical slot in each of said trammel attachment members extending horizontally and perpendicular with respect to said horizontally extending angular scale receiving openings, and a flat scale slidably receivable, selectively in said slot, said angular scale securing means being operative to secure said flat scale in selectively adjusted position with respect to said trammel attachment members.

5. The invention as defined in claim 4 wherein said securing means comprises a thumb screw threaded through the top of each of said trammel attachment members and arranged to press against the top edge of said flat scale when in selected position in said slots.

6. The invention as defined in claim 4 wherein said vertical slot is formed at a central vertical position therealong with a circular horizontally extending widened portion, and a metal scribe having a cylindrical body portion adapted to slidihgly fit in through said circular widened portion and be selectively secured therein in adjusted position by said securing means.

7. The invention as defined in claim 6 including a stem member extending downwardly from the lower end of each of said trammel members, a pencil lead, removably attached to the outer end of one of said stem members and a steel pin removably attached to the outer end of the other of said stern members.

Hickok Oct. 13,1885 Taylor 'May 1, 1900 

